Now that the weather allows us to be outside again, remember – sunburn can double your risk of skin cancer.
SPF is not an indication of how much time you can spend in the sun. For example, if you use a sunscreen with an SPF 30 rather than one with an SPF 15, it doesn’t mean you can stay in the sun twice as long. In reality, an SPF of 15 filters out about 93 percent of the UVB rays; SPF 30 filters about 97 percent of UVB rays.
Don’t rely on the SPF factor to decide how long you’re safe in the sun. And don’t count on your skin to tell you when you’ve had too much sun. It may take up to 24 hours for a sunburn to develop fully. Reapply sunscreen frequently!
How much sunscreen is necessary, and how often should it be applied?
Most people use sunscreen too sparingly. A liberal application is 1 ounce — the amount in a shot glass — to cover all exposed parts of the body. If you have a 4-ounce bottle, you’ll be using about one-fourth of it for one application. Be sure to rub the sunscreen in well.
To maximize protection, apply sunscreen liberally 30 minutes before going outdoors and reapply every two hours, or as needed.
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